A Big Band is a type of musical ensemble associated with playing jazz music and which became popular during the Swing Era from the early 1930s until the late 1940s. Big Bands evolved with the times and continue to today. A big band typically consists of approximately 12 to 25 musicians and contains saxophones, trumpets, trombones, and a rhythm section. The terms jazz band, jazz ensemble, stage band, jazz orchestra, society band and dance band may be used to describe a specific type of big band.

In contrast to smaller jazz combos, in which most of the music is improvised, or created spontaneously, music played by big bands is highly "arranged", or prepared in advance and notated on sheet music. The music is traditionally called 'charts'. Improvised solos may be played only when called for by the arranger.

History and style

There are two distinct periods in the history of popular bands. Beginning in the mid-1920s, big bands, then typically consisting of 10–25 pieces, came to dominate popular music. At that time they usually played a sweet form of jazz that involved very little improvisation, which included a string section with violins, which was dropped after the introduction of swing in 1935. The dance form of jazz was characterized by a sweet and romantic melody. Orchestras tended to stick to the melody as it was written and vocals would be sung (often in a tenor voice) and in tune with the melody.